Question

How much is 30% of 30000

Answer 1

30 percent of 30000 is 9000

Answer 2

30% of 30000 =9000

We assume that the number 30000 is 100% because it's the output value of the task. 
We assume that x is the value we are looking for
If 30000 is 100% so we can write it down as 30000=100%
We know that x is 30% of the output value so we can write it down as x=30%. 
Now we have two simple equations
1) 30000=100%
2) x=30%
where left sides of both of them have the same units and both right sides have the same units so we can do something like that
30000/x=100%/30% Now we just have to solve the simple equation and we will get the solution we are looking for
Solution for what is 30% of 30000

30000/x=100/30
(30000/x)*x=(100/30)*x       we multiply both sides of the equation by x
30000=3.33333333333*x        we divide both sides of the equation by (3.33333333333) to get x
30000/3.33333333333=x 
9000=x 
x=9000

now we have: 
30% of 30000=9000